2G Over 4G RRH RFFE Combining Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies do not effectively enable the transmission and reception of 2G/3G signals over LTE/5G radio heads in V-RAN architecture, lacking direct methods to multiplex these signals independently and handle split options.
Innovation Solution
A radio frequency front end (RFFE) system comprising a 2G GSM transceiver, 4G LTE transceiver, and a combiner that upsamples 2G signals to a 4G carrier frequency, allowing transmission of both 2G and 4G on the same frequency band, using a common public radio interface (CPRI) or enhanced CPRI interface, and incorporating a 5G New Radio (NR) transceiver for simultaneous operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If 2G and 4G signals are transmitted on separate frequency bands using traditional architecture, then signal transmission is reliable, but device complexity and spectrum utilization are suboptimal
Solution Approach 1:
The patent combines 2G and 4G transceiver chains into a single integrated RFFE unit that shares common RF front-end components, power amplifiers, and antenna interfaces. This merging allows multiple RATs to coexist on the same hardware platform, reducing overall device complexity while maintaining multi-RAT transmission capability through digital signal processing and combiner circuits.
Solution Approach 2:
The RFFE is designed as a universal platform that can handle multiple radio access technologies (2G GSM, 4G LTE, and potentially 5G NR) through a single device. The system uses configurable transceiver chains and programmable signal processing to adapt to different RAT requirements, eliminating the need for separate dedicated hardware for each technology and enabling flexible spectrum utilization.
2Productivity
If 2G signals are upsampled to 4G carrier frequency for combined transmission, then spectrum utilization improves, but signal processing complexity increases
Solution Approach 1:
The system dynamically changes signal parameters including sampling rates, carrier frequencies, and modulation schemes to optimize spectrum utilization. The 2G signals are upsampled to 4G carrier frequencies with configurable sampling rates (e.g., 30.72 MHz, 38.4 MHz, or 76.8 MHz) depending on the specific deployment scenario, allowing flexible adaptation to different spectrum conditions and network requirements.
3Adaptability or versatility
If separate virtual MAC addresses are implemented for different RATs, then network compatibility is enhanced, but control plane complexity increases
Solution Approach 1:
The control plane is segmented into multiple virtual MAC address spaces, each dedicated to a specific RAT (2G, 4G, 5G). This segmentation allows independent management of control plane functions for each technology while sharing the same physical hardware. Each virtual MAC address handles RAT-specific signaling and control procedures, ensuring protocol compatibility without requiring a single monolithic control structure.
Data Source
AI summary
Various embodiments of a radio frequency front end (RFFE) are disclosed, in one embodiment comprising: a 2G Global System for Mobile telecommunications (GSM) transceiver; a 4G Long Term Evolution (LTE) transceiver; and a combiner coupled to the 2G GSM transceiver and to the 4G LTE transceiver and to a radio head, coupled to the radio head via at least one stream of IQ samples, the at least one stream carrying samples derived from the 2G GSM transceiver and samples derived from the 4G LTE transceiver. The RFFE may be configured to provide downlink for 2G and 4G. The combiner may be configured to upsample 2G signals from the 2G GSM transceiver to a 4G carrier frequency. The RFFE may be configured to transmit both 2G and 4G on a same frequency band.